In a rail vehicle, as an example of a vehicle for conveying passengers, it is known to make the air conditioning duct extended in an intermediate space which is bounded by an intermediate ceiling of the rail vehicle and its roof. This intermediate space runs in the longitudinal direction of the rail vehicle, as does the air conditioning duct. With respect to fire protection, the regulation EBC 7900 01 05 must be complied with, according to which regulation partitions have to be provided at regular intervals in the intermediate space in order to delay the propagation of flames and hot gases.
In order to comply with these regulations, metal partitions have previously been used to seal off the intermediate space, said metal partitions enclosing the air conditioning duct and being sealed off from the walls of the intermediate space.